Canadian utility Manitoba Hydro seeks bids to perform core drilling on the spillway and concrete dam of the 165-MW Seven Sisters hydroelectric project in Manitoba. Bids are due June 5.

Manitoba Hydro called for bids May 20for circuit breakers and switchgear modifications at Seven Sisters and the 479-MW Grand Falls project. It took bids in Aprilfor a broad range of civil engineering services to its dams, hydroelectric projects and other facilities in Manitoba.

Seven Sisterswas built in 1952 on the Winnipeg River and includes six generating units.

Manitoba Hydro seeks bids for diamond core drilling to recover a 6-inch-diameter, 10-foot-long horizontal concrete core from eight locations of the downstream rollway of the spillways as well as a 2.5-inch-diameter, 65-foot-long vertical concrete and rock foundation core from two locations on the deck of the south non-over dam. Other work includes additional core drilling and inspection and testing of the cored holes. The work is to be completed by October 2014.